1351663665 has 32 divisors (see below), whose sum is σ = 2374935552. Its totient is φ = 651000000.

The previous prime is 1351663619. The next prime is 1351663699. The reversal of 1351663665 is 5663661531.

It is not a de Polignac number, because 1351663665 - 2⁸ = 1351663409 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2211 + ... + 52040.

It is an arithmetic number, because the mean of its divisors is an integer number (74216736).

Almost surely, 2^1351663665 is an apocalyptic number.

1351663665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1351663665 is a deficient number, since it is larger than the sum of its proper divisors (1023271887).

1351663665 is a wasteful number, since it uses less digits than its factorization.

1351663665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54421.

The product of its digits is 291600, while the sum is 42.

The square root of 1351663665 is about 36764.9787841636. The cubic root of 1351663665 is about 1105.6632628001.

It can be divided in two parts, 135166 and 3665, that added together give a palindrome (138831).

The spelling of 1351663665 in words is "one billion, three hundred fifty-one million, six hundred sixty-three thousand, six hundred sixty-five".